1. Field
Embodiments of the present invention relate to an organic light-emitting display device, and more particularly, to an organic light-emitting display device that has improved extraction efficiency and viewing angle characteristics.
2. Description of Related Art
In general, an organic light-emitting display device realizes colors by recombining holes and electrons, which are injected from an anode and a cathode to an emission layer, and has a structure in which the emission layer is interposed between a pixel electrode serving as the anode and an opposite electrode serving as the cathode.
A unit pixel of an organic light-emitting display device includes three sub-pixels: red, green, and blue sub-pixels. A desired color is realized by appropriately combining the three sub-pixels. That is, for each respective sub-pixel, an emission layer that emits one of the red, green, or blue colors is interposed between two electrodes, and a color of a unit pixel is realized by appropriately combining three respective color light beams.
Recently, a resonating structure in each sub-pixel has been developed, in order to improve the extraction efficiency of an organic light-emitting display device. That is, the resonating structure is configured so that a semi-transmissive electrode is formed at a side of one of the anode or the cathode, towards which an image is realized, and a total reflective electrode is formed at a side of the other one of the anode or the cathode. Thus, light beams constructively interfere with each other while reciprocating between the anode and the cathode, and light that is significantly enhanced may be extracted from each sub-pixel.
However, if a resonating structure is used in an organic light-emitting display device, the extraction efficiency of the organic light-emitting display device is improved, but the viewing angle characteristics of the organic light-emitting display device are degraded. That is, if a resonating structure is used in an organic light-emitting display device, luminance of the organic light-emitting display device may be reduced and/or color shift may become a concern depending on a viewer's viewing angle.